Electric plaster-finishing trowel

ABSTRACT

A portable electric motor driven plaster finishing device having a pair of sockets to selectively receive a shaft terminating in a troweling plate universally connected to the shaft. The device includes a transmission which will oscillate the shaft and a troweling plate when the latter is positioned in one socket and the device energized to form a first type of variegated pattern in uncured planar plaster surfaces. The transmission is also adapted to rotate the shaft and troweling plate when the shaft is placed in the second socket for forming different types of patterns on uncured planar plaster surfaces.

finite tates [45] Patented Dec.21,1971

[54] ELECTRIC PLASTER-FHNISHING TROWElL 2 Claims, 13 Drawing Figs.

25/1045, 94/45 [51] 1nt.Cl lE04f21/16 [50] Field ofSearch 15l3,4,93,

235.6, 236, 235.4; 25/1045; 30/1649; 1 18/1 I 1; 74/22, 22 A, 48; 94/45, 45 R, 45 A, 45 MO, 46, 46

2,745,653 5/1956 Deason 15/93 R X 3,025,549 3/1962 Turner et a1. 15/235.6

3,406,417 10/1968 Niles et a1. 15/4 FOREIGN PATENTS 1,100,897 4/1955 France 94/45 1,082,475 9/1967 Great Britain 15/235.4

Primary ExaminerLeon G. Machlin At1arneyL1oyd J. Andres ABSTRACT: A portable electric motor driven plaster finishing device having a pair of sockets to selectively receive a shaft terminating in a troweling plate universally connected to the shaft. The device includes a transmission which will oscillate the shaft and a troweling plate when the latter is positioned in one socket and the device energized to form a first type of variegated pattern in uncured planar plaster surfaces. The transmission is also adapted to rotate the shaft and troweling plate when the shaft is placed in the second socket for forming different types of patterns on uncured planar plaster surfaces.

WENYEU DECZY rem SHEET 1 BF 4 INVENTOR. EDWIN PADGETT PATENTEU m2? I97! SHEET 2 0F 5 INVENTOR. EDWIN PADGETT WENTEDnEcmEm 3,628,210

sum 3 HF d 2 3 INVENTOR.

EDWIN PADGETT ELECTRIC FLAS'IER-FINISIIIING 'lllltOWElL This invention relates in general to plastering devices and more particularly to a device for applying artistic surface finished to uncured plaster surfaces.

Prior to this invention, artistic patterns were applied to uncured plaster areas by manual troweling, which required a relatively high degree of skill and the consumption of considerable time.

The present invention considerably reduces the above mentioned skill requirement and is accomplished at a great saving in time.

A principal object of the invention is the provision of a portable electric device which includes a troweling plate which is power driven in a rotary or an oscillating motion to produce a wide variety of artistic embossment on uncured plaster surfaces.

A further object of the invention is the provision of a manually operated motor driven device which will selectively rotate or oscillate a troweling plate for manual operation which will permit manual finishing of large areas of walls without the use of ladders or scaffolds.

These and other objects and advantages in one embodiment of the invention are described and shown in the following specification and drawings, in which:

FIG. l is a perspective view of the plaster finishing plate in reduced scale.

FIG. 2 is an enlarged perspective view of the underside of the plate shown in FIG. ll.

FIG. 3 is an enlarged cross-sectional plan view taken through section line 3--3, FIG. 11.

FIG. 4 is a fragmentary enlarged cross-sectional view taken through section line 4-4, FIG. ll.

FIG. 5 is an enlarged cross-sectional plan view taken through section line 5-5, FIG. 11.

FIG. 6 is the same as FIG. 1 with elements in changed position.

FIG. 7 is a perspective view of an alternate troweling plate assembly for use in the device shown in FIG. 11.

FIG. 8 is an enlarged cross sectional view taken through section line 8--3, FIG. 7.

FIG. 9 illustrates one of the positions of the device when used for applying afinished variegation on a vertical wall.

FIG. 10 illustrates a typical ornamental pattern obtained with the troweling plate shown in FIGS. I and 6, when oscillated.

FIG. llll illustrates a typical ornamental pattern obtained when the troweling plate shown in FIGS. 1 and 6 is rotated.

FIG. I2 illustrates a typical pattern when the troweling plate shown in FIGS. 7 and 8 is oscillated.

FIG. 13 illustrates a typical pattern when the troweling plate shown in FIGS. 7 and I3 is rotated.

Referring to FIG. I, an electric motor 11 supplied with power by a cord 2 has an integral gear housing 3 on the drive end thereof with an oblique integral handle 3 offset, as shown. A transmission cover 5 includes an integral pair of parallel adjaccnt bearing supports 6 and 7 with the bores therein parallel to the axis of the motor shaft, not shown. A tubular troweling plate shaft 8 is engaged in bearing support 6 by means hereinafter described and terminates at the upper end in a rectangular troweling plate 9 having a planar upper surface terminating in radiused edges.

Referring to FIG. 2, the shaft 8 is centrally secured to the underside of the troweling plate by an arcuate link It) having a straight portion 11 journaled for rotation about axis a-a normal to the axis of a boss 12 integral with the trowel 9. The opposite straight end portion 13 of the link isjournaled for rotation about axis b--b in an insert 14 normal to the shaft 3 which provides a limited motion universal joint between the shaft d and plate 9.

Referring to FIGS. 3 and 4, the motor shaft 15 terminates in a pinion gear 116 in housing 3. A pair of like gears I7 and 18 have secured therein coaxial shafts l9 and 20, respectively, which shafts are retained forrotation in ball bearing assemblies 21 and 22. Thus, when the motor is energized, the gears l7 and 13 will rotate in the same direction at a predetermined speed as shown by arrows in FIG. 5.

Referring to FIGS. 3 and 4, a crank pin 23 in gear I7 is engaged by a fork 245, which is secured to the double D lower end of a clutch member 25 by well known C washer means. The clutch member is journaled for oscillation in a radial ball hearing 26 and an axial ball thrust bearing 27, which are retained in the housing cover 5 in the position shown. Thus when the gear I7 is rotated, the fork 2 1i and the clutch member 25 will oscillate through a predetermined angle, as indicated by dotted lines in FIG. 3. The upper end of clutch member 25 terminates in a socket 23 with a transverse slot 29 through opposite sides thereof to receive a pin 30 secured through the lower end portion of a removable insert shaft 31. The lower end of the shaft 31l has a coaxial pilot 32;, of smaller diameter as shown. The upper end portion of shaft 311 is journaled in a radial ball bearing 33. An enlarged upper end portion 34 of the shaft is secured in tubular extension shaft 8, as shown. Thus it is apparent that when the motor is energized, the shaft 3 and the troweling plate 9 will oscillate and the universal coupling link It] will accommodate itself to a planar surface through wide angles of universal direction of the drive device, as shown in dotted lines in FIG. 4, by the operation of the universaljoint link It).

Again referring to FIG. 4, the gear 118 has secured therein a coaxial extension 33 with a double D socket therein, better shown in FIG. 5, in which a second clutch member 34 is secured and journaled in cover 5 by a ball thrust bearing 35. The upper end of the clutch member 34l also has a transverse slot 29 and a bore to receive the lower pilot and pin portion of the shaft 31. The upper end 36 of. the second clutch member has a transverse slot 29 therethrough like that in member 28. The support 7 has an upper radial ball bearing 37 for supporting the upper portion of the shaft 3i when transferred to engage clutch member 34 for the constant rotation of the troweling plate, as illustrated in FIG. 6.

Referring to FIGS. 7 and 3, another form of troweling plate 38 is provided with equispaced spherical projections 39 extending a relatively small distance outward from the planar portion of the plate, as shown, which will produce different forms or ornamental patterns on uncured planar plaster than does the planar troweling plate shown in FIG. 6.

In operation and referring to FIG. 3, each troweling plate is operated by placing the face thereof against the uncured plastered wall and energizing the device, which will impart either the oscillating angular motion or the rotary motion to the plate depending on whether the shaft of the plate is inserted in the support 6 or 7 and then. manually moving the device in predetermined regular patterns across the surface of the plaster and thus embossing a repetition of one of several kinds of ornamental patterns in the surface of the plaster, such as illustrated in FIGS. ll0l3.

FIGS. It) and 12 illustrate forms of figurations made with planar and spherical projection plates, respectively. FIGS. 11 and 112 illustrate forms of figurations made with the spherical projection plates, respectively.

This invention comprehends modifications that come within the teachings and spirit of the above specification.

Having described my invention, I claim:

II. A portable electric plaster finishing device comprising means forming a housing,

a first open socket means journaled in said housing for rotation about a predetermined first axis,

a second like open socket means journaled for oscillation in said housing about a second axis parallel said first axis,

an electric motor secured to said housing for driving said device,

a transmission means in said housing connecting said motor with said first and second socket means for rotating said first socket about its said axis and oscillating said second socket means through a predetermined angle about said second axis when said motor is energized,

a plaster finishing plate having a planar outer finishing surface,

pattern on uncured plaster when manually moved with a predetermined motion over an area of uncured plaster.

2. The construction recited in claim 1 including a handle secured to said housing for engagement by the human hand to manually operate the said device when energized. 

1. A portable electric plaster finishing device comprising means forming a housing, a first open socket means journaled in said housing for rotation about a predetermined first axis, a second like open socket means journaled for oscillation in said housing about a second axis parallel said first axis, an electric motor secured to said housing for driving said device, a transmission means in said housing connecting said motor with said first and second socket means for rotating said first socket about its said axis and oscillating said second socket means through a predetermined angle about said second axis when said motor is energized, a plaster finishing plate having a planar outer finishing surface, a straight finishing plate shaft of predetermined length, one end of said shaft adapted and constructed for manual selective engagement in either said first or said second socket means, a universal joint connecting said other end of said shaft to the under side of said plate whereby said finishing surface of said plate will emboss a selected predetermined artistic pattern on uncured plaster when manually moved with a predetermined motion over an area of uncured plaster.
 2. The construction recited in claim 1 including a handle secured to said housing for engagement by the human hand to manually operate the said device when energized. 